Control arms - just lowers or both?
 

I want to put some control arms on - what's the advantage to uppers AND lowers -vs- just putting lowers on? I'm starting to run low on cash and if the lowers only will do the trick I'll go with that - more money for my sub-frames. Also, at what point do I start worrying about ripping my torque boxes? Am I OK with street tires or should I weld them now?

------------------
86 GT, GT40P heads, Cobra cam, 1.7 RR's, Cobra intake, 65mm TB, 73mm Vortech, 24# injectors, MAC GT40P headers, 2-1/2" BBK H-pipe (w/cats), Flowmasters, 3.55s.
**************
Crane 2031 on order

Depends on your application for the most part. Is this a street machine, drag racer or road racer? I understand that the lowers are most important in launching in a straight line and the uppers are more critical in controlling sway in sharp turns. I've got the Factory Five lowers installed on mine and I'll do the uppers when I accumulate more patience as the bolts are rusted f-ing shut. Most of the guys I know who are into carving corners have gone with the more expensive adjustable control arms that they can "tune" to road conditions. If your going to throw on sub frames I would think it would be no big deal to have the torque boxes welded at the same time, but that's just a guess.

------------------
91 LX 5.0
Z t-5, 3:73 gear, Vortech 73mm Mass Air, Accufab 65mm TB, BBK underdrives, Crane HI-6S Ignition, BBK unequal length headers, Bassani x pipe, 2.5" Dynomax Super Turbo cat back, Kenny Brown Super Subs, Factory Five Control Arms, Mac cold air kit and more to come!

Just get the lowers. My friend ran 10's in the quarter with stock uppers. You really dont need the uppers, lowers are more important. Welding the torque boxes is easily done by anyone who can weld in about three minutes. Have it done when you weld in subframe connecters.

------------------
1993 GT/AOD
'93 Mustang GT

As long as bushings are not worn out on the upper arms the lower control arms are all you need to replace. If you are going to be running slicks you might look at a set that are adjustable, these will allow the clearance for the larger tires.

------------------
89 (GR40 Griggs)Hatch
89 Coupe
90 Coupe

I'm almost done asking questions about control arms and torque boxes. From the answers I got here and in my post on torque boxes, do I understand that the most stress is placed on the lower torque boxes and I only need to weld those? The uppers are OK to leave alone? Thanks for all the info.
Chris

Ya, I had my torque boxes welded up when I put subframe connectors in. Just don't use an arc welder... the metal is pretty thin...

The stock 4 link sucks. It's all compromise... using them to control lateral movement causes all kinds of bind.

The uppers do provide awesome anti-squat on these front heavy, RWD cars... but they cause bind, and aweful rear brake jacking.

For the strip, keep them. If you wanna turn corners, think about removing them, and go with a panhard bar & torque arm (or parallel 4 link). This lowers the rear roll center, so the front end isn't always overloaded (reducing the understeer). It also requires stiffer rear springs... so you can also go a little lower, without bottoming out all the time.

That'll probably blow the budget, so for starters, get some good lowers. Spherical bushings on one end will really reduce bind. The global west arms are decent, if that's all you'll ever do... but they won't work with a PHB, so keep that in mind.

Just ordered Central Coast Mustang lower control arms and sub-frame connectors. Between that, the cam and the h-pipe, I just gotta keep the credit card statement outta the wife's hands. :< )

------------------
86 GT, GT40P heads, Cobra cam, 1.7 RR's, Cobra intake, 65mm TB, 73mm Vortech, 24# injectors, MAC GT40P headers, 2-1/2" BBK H-pipe (w/cats), Flowmasters, 3.55s.
**************
Crane 2031 on order